CARTR Plus: the creation of an ART registry in Canada

STUDY QUESTION

What is the status of fertility treatment and birth outcomes documented over the first 6 years of the Canadian Assisted Reproductive Technologies Register (CARTR) Plus registry?

SUMMARY ANSWER

The CARTR Plus registry is a robust database containing comprehensive Canadian fertility treatment data to assist with providing evidence-based rationale for clinical practice change.

WHAT IS KNOWN ALREADY

The rate of infertility is increasing globally and having data on fertility treatment cycles and outcomes at a population level is important for accurately documenting and effecting changes in clinical practice.

STUDY DESIGN, SIZE, DURATION

This is a descriptive manuscript of 183 739 fertility treatment cycles from 36 Canadian clinics over 6 years from the CARTR Plus registry.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Canadian ART treatment cycles from 2013 through 2018 were included. This manuscript described trends in type of fertility treatment cycles, pregnancy rates, multiple pregnancy rates, primary transfer rates and birth outcomes.

MAIN RESULTS AND THE ROLE OF CHANCE

Over the 6 years of the CARTR Plus registry, the number of treatment cycles performed ranged from less than 200 to greater than 1000 per clinic. Patient age and the underlying cause of infertility were two of the most variable characteristics across clinics. Similar clinical pregnancy rates were found among IVF and frozen embryo transfer (FET) cycles with own oocytes (38.9 and 39.7% per embryo transfer cycle, respectively). Fertility treatment cycles that used donor oocytes had a higher clinical pregnancy rate among IVF cycles compared with FET cycles (54.9 and 39.8% per embryo transfer cycle, respectively). The multiple pregnancy rate was 7.4% per ongoing clinical pregnancy in 2018, which reflected a decreasing trend across the study period. Between 2013 and 2017, there were 31 811 pregnancies that had live births from all ART treatment cycles, which corresponded to a live birth rate of 21.4% per cycle start and 89.1% of these pregnancies were singleton live births. The low multiple pregnancy rate and high singleton birth rate are associated with the increase in single embryo transfers.

LIMITATIONS, REASONS FOR CAUTION

There is potential for misclassification of data, which is present in all administrative health databases.

WIDER IMPLICATIONS OF THE FINDINGS

The CARTR Plus registry is a robust resource for ART data in Canada. It provides easily accessible aggregated data for Canadian fertility clinics, and it contains data that are internationally comparable.

STUDY FUNDING/COMPETING INTEREST(S)

There was no funding provided for this study. The authors have no competing interests to declare.

Reactive oxygen species in status epilepticus

There has been growing evidence for a critical role of oxidative stress in neurodegenerative disease, providing novel targets for disease modifying treatments. Although antioxidants have been suggested and tried in the treatment of epilepsy, it is only recently that the pivotal role of oxidative stress in the pathophysiology of status epilepticus has been recognized. Although conventionally thought to be generated by mitochondria, reactive oxygen species during status epilepticus and prolonged seizure are generated mainly by NADPH (nicotinamide adenine dinucleotide phosphate) oxidase (stimulated by NMDA receptor activation). Excessive production of reactive oxygen species results in lipid peroxidation, DNA damage, enzyme inhibition, and mitochondrial damage, culminating in neuronal death. Antioxidant therapy has been hampered by poor CNS penetration and rapid consumption by oxidants. However, alternative approaches such as inhibiting NADPH oxidase or increasing endogenous antioxidant defenses through activation of the transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) could avoid these problems. Small molecules that increase Nrf2 activation have proven to be not only effective neuroprotectants following status epilepticus, but also potently antiepileptogenic. There are "Proceedings of the 7th London-Innsbruck Colloquium on Status Epilepticus and Acute Seizures".

Decreasing the risk of sudden unexpected death in epilepsy: structured communication of risk factors for premature mortality in people with epilepsy

BACKGROUND AND PURPOSE

Good practice guidelines highlight the importance of making people with epilepsy aware of the risk of premature mortality in epilepsy particularly due to sudden unexpected death in epilepsy (SUDEP). The SUDEP and Seizure Safety Checklist ('Checklist') is a structured risk communication tool used in UK clinics. It is not known if sharing structured information on risk factors allows individuals to reduce SUDEP and premature mortality risks. The aim of this study was to ascertain if the introduction of the Checklist in epilepsy clinics led to individual risk reduction.

METHODS

The Checklist was administered to 130 consecutive people with epilepsy attending a specialized epilepsy neurology clinic and 129 attending an epilepsy intellectual disability (ID) clinic within a 4-month period. At baseline, no attendees at the neurology clinic had received formal risk advice, whereas all those attending the ID clinic had received formal risk advice on multiple occasions for 6 years. The Checklist was readministered 1 year later to each group and scores were compared with baseline and between groups.

RESULTS

Of 12 risk factors considered, there was an overall reduction in mean risk score for the general (P = 0.0049) but not for the ID (P = 0.322) population. Subanalysis of the 25% of people at most risk in both populations showed that both sets had a significant reduction in risk scores (P < 0.001).

CONCLUSION

Structured discussion results in behavioural change that reduces individual risk factors. This impact seems to be higher in those who are at current higher risk. It is important that clinicians share risk information with individuals as a matter of public health and health promotion.

Non-Convulsive Status Epilepticus Presenting as a Psychiatric Condition

Non-convulsive status epilepticus may present as confusion, behavioural disturbances and psychiatric conditions. We present the case of a 17-year-old man who had episodes of non-convulsive status epilepticus as his only manifestation of epilepsy which was mis-diagnosed as a psychiatric condition for over 10 years. He has had almost complete resolution of his symptoms with the introduction of carbamazepine. Non-convulsive status epilepticus is probably commoner than previously thought, and should be considered as a possible diagnosis in all patients presenting with prolonged episodes of altered consciousness even without other manifestations of epilepsy.

Maternal pre-gravid cardiometabolic health and infant birthweight: A prospective pre-conception cohort study

BACKGROUND AND AIMS

Both low birthweight and high birthweight have been associated with the development of cardiometabolic disease in adulthood, possibly reflecting the effect of intrauterine fetal programming. As developmental programming can begin before conception, pre-gravid factors that predict birthweight may be relevant in this context. However, little is known about such factors. Thus, we established a pre-conception cohort to identify maternal pre-gravid cardiometabolic determinants of infant birthweight.

METHODS AND RESULTS

In this prospective observational cohort study, 1484 newly-married women in Liuyang, China, underwent baseline (pre-gravid) evaluation and then were followed across a subsequent pregnancy. Pre-gravid cardiometabolic characterization consisted of clinical (anthropometry, blood pressure) and biochemical evaluation (total/LDL/HDL cholesterol, triglycerides, glucose) at median 20 weeks before a singleton pregnancy. Mean birthweight was 3294 ± 444 g, with 173 neonates large-for-gestational-age (LGA) and 110 small-for-gestational-age (SGA). On multiple linear regression analysis, positive determinants of birthweight were maternal age, pre-gravid body mass index (BMI), weight gain in pregnancy, length of gestation, and male infant (all p ≤ 0.0003). On logistic regression analysis, independent predictors of an LGA delivery were maternal age (OR = 1.10 per year, 95%CI 1.03-1.18), pre-gravid BMI (OR = 1.21 per kg/m², 1.07-1.37), and gestational weight gain (OR = 1.10 per kg, 1.06-1.14). The only independent predictor of SGA was gestational weight gain (OR = 0.93 per kg, 0.89-0.97).

CONCLUSION

Maternal weight before and during pregnancy is the predominant cardiometabolic determinant of infant birthweight, rather than pre-gravid blood pressure, glucose or lipid profile.

A case of pure gelastic seizures due to hypothalamic hamartoma with a benign course

Hypothalamic hamartoma is a potentially complex entity with diverse clinical manifestations. We report a case of gelastic seizures associated with a hypothalamic hamartoma, which followed a benign course. A 31-year-old woman with episodes of laughter was referred for diagnostic evaluation. Her initial MRI and EEG were reported as normal. However, her episodes of laughter were typical of gelastic seizures from history and video review. Repeat MRI revealed a small HH. She declined any medical treatment and was medication free until last follow-up. This benign course of HH-associated epilepsy, not necessitating treatment, to our knowledge, has not been previously reported.

A study of the electro-haemodynamic coupling using simultaneously acquired intracranial EEG and fMRI data in humans

In current fMRI studies designed to map BOLD changes related to interictal epileptiform discharges (IED), which are recorded on simultaneous EEG, the information contained in the morphology and field extent of the EEG events is exclusively used for their classification. Usually, a BOLD predictor based on IED onset times alone is constructed, effectively treating all events as identical. We used intracranial EEG (icEEG)-fMRI data simultaneously recorded in humans to investigate the effect of including any of the features: amplitude, width (duration), slope of the rising phase, energy (area under the curve), or spatial field extent (number of contacts over which the sharp wave was observed) of the fast wave of the IED (the sharp wave), into the BOLD model, to better understand the neurophysiological origin of sharp wave-related BOLD changes, in the immediate vicinity of the recording contacts. Among the features considered, the width was the only one found to explain a significant amount of additional variance, suggesting that the amplitude of the BOLD signal depends more on the duration of the underlying field potential (reflected in the sharp wave width) than on the degree of neuronal activity synchrony (reflected in the sharp wave amplitude), and, consequently, that including inter-event variations of the sharp wave width in the BOLD signal model may increase the sensitivity of forthcoming EEG-fMRI studies of epileptic activity.

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First study of EEG morphology using simultaneous intracranial EEG-fMRI in humans

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The duration of sharp waves is significantly correlated with the BOLD signal amplitude.

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BOLD amplitude reflects more field potential duration than neuronal synchrony.

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Sharp wave duration should be included in BOLD models of epileptic discharges.

Antiviral medication use in a cohort of pregnant women during the 2009-2010 influenza pandemic

Preventing influenza-like illness (ILI) during pregnancy with antiviral medication use (AVMU) can mitigate serious health risks to mother and foetus. We report on AVMU in pregnant women in Ontario, Canada, and describe characteristics of AVMU during the 2009-2010 H1N1 pandemic. Rates and risk estimates of AVMU were compared across multiple categories and stratified across ILI infection status. Increased AVMU was observed in women with influenza infections, active smokers, those vaccinated against influenza, and those with pre-existing co-morbidities. Decreased AVMU was observed in women with multiple gestations, and those in neighbourhoods of high immigrant concentrations. Our stratified analysis indicated that the observed patterns differed by ILI infection status. We demonstrated that once infected, women across multiple groups were equally likely to use antiviral medications. In this report we also propose possible clinical explanations for the observed differences in AVMU, which will be useful in planning prevention initiatives for future pandemics.

Seizure activity results in calcium- and mitochondria-independent ROS production via NADPH and xanthine oxidase activation

Seizure activity has been proposed to result in the generation of reactive oxygen species (ROS), which then contribute to seizure-induced neuronal damage and eventually cell death. Although the mechanisms of seizure-induced ROS generation are unclear, mitochondria and cellular calcium overload have been proposed to have a crucial role. We aim to determine the sources of seizure-induced ROS and their contribution to seizure-induced cell death. Using live cell imaging techniques in glioneuronal cultures, we show that prolonged seizure-like activity increases ROS production in an NMDA receptor-dependent manner. Unexpectedly, however, mitochondria did not contribute to ROS production during seizure-like activity. ROS were generated primarily by NADPH oxidase and later by xanthine oxidase (XO) activity in a calcium-independent manner. This calcium-independent neuronal ROS production was accompanied by an increase in intracellular [Na(+)] through NMDA receptor activation. Inhibition of NADPH or XO markedly reduced seizure-like activity-induced neuronal apoptosis. These findings demonstrate a critical role for ROS in seizure-induced neuronal cell death and identify novel therapeutic targets.

Is thrombophilia associated with placenta-mediated pregnancy complications? A prospective cohort study

BACKGROUND

Case control studies suggest that genetic thrombophilias increase the risk of placenta-mediated pregnancy complications (pregnancy loss, small for gestational age (SGA), preeclampsia and/or placental abruption). Cohort studies have not supported this association but were underpowered to detect small effects.

OBJECTIVE

To determine if factor V Leiden (FVL) or the prothrombin gene mutation (PGM) were associated with placenta-mediated pregnancy complications.

PATIENTS/METHODS

A prospective cohort of unselected, consenting pregnant women at three Canadian tertiary care hospitals had blood drawn in the early second trimester and were genotyped for FVL and PGM after delivery. The main outcome measure was a composite of pregnancy loss, SGA < 10th percentile, preeclampsia or placental abruption.

RESULTS

Complete primary outcome and genetic data were available for 7343 women. Most were Caucasian (77.7%, n = 5707), mean age was 30.4 (± 5.1) years, and half were nulliparous. There were 507 (6.9%) women with FVL and/or PGM; 11.64% had a placenta-mediated pregnancy complication. Of the remaining 6836 women, 11.23% experienced a complication. FVL and/or PGM was associated with a relative risk of 1.04 (95% CI, 0.81-1.33) for the composite outcome, with similar results after adjustment for important covariates.

CONCLUSIONS

Carriers of FVL or PGM are not at significantly increased risk of these pregnancy complications.

Evaluation of the impact of fetal fibronectin test implementation on hospital admissions for preterm labour in Ontario: a multiple baseline time-series design

OBJECTIVE

To determine the impact of a health system-wide fetal fibronectin (fFN) testing programme on the rates of hospital admission for preterm labour (PTL).

DESIGN

Multiple baseline time-series design.

SETTING

Canadian province of Ontario.

POPULATION

A retrospective population-based cohort of antepartum and delivered obstetrical admissions in all Ontario hospitals between 1 April 2002 and 31 March 2010.

METHODS

International Classification of Diseases codes in a health system-wide hospital administrative database were used to identify the study population and define the outcome measure. An aggregate time series of monthly rates of hospital admissions for PTL was analysed using segmented regression models after aligning the fFN test implementation date for each institution.

MAIN OUTCOME MEASURE

Rate of obstetrical hospital admission for PTL.

RESULTS

Estimated rates of hospital admission for PTL following fFN implementation were lower than predicted had pre-implementation trends prevailed. The reduction in the rate was modest, but statistically significant, when estimated at 12 months following fFN implementation (-0.96 hospital admissions for PTL per 100 preterm births; 95% confidence interval [CI], -1.02 to -0.90, P = 0.04). The statistically significant reduction was sustained at 24 and 36 months following implementation.

CONCLUSIONS

Using a robust quasi-experimental study design to overcome confounding as a result of underlying secular trends or concurrent interventions, we found evidence of a small but statistically significant reduction in the health system-level rate of hospital admissions for PTL following implementation of fFN testing in a large Canadian province.

Preeclampsia and gestational diabetes mellitus: pre-conception origins?

Preeclampsia (PE) and gestational diabetes mellitus (GDM) are two of the most common medical complications of pregnancy, with risks for both mother and child. Like many other antepartum complications, PE and GDM occur only in pregnancy. However, it is not clear if pregnancy itself is the cause of these complications or it these conditions are caused by factors that existed prior to gestation. In this paper, we hypothesize that although the clinical findings of PE and GDM are first noted during pregnancy, the origins of both conditions may actually precede pregnancy. We further hypothesize that pathophysiologic changes underlying PE and GDM are present prior to pregnancy, but remain undetected in the non-gravid state either because pregnancy is the trigger that makes these pathologies become clinically detectable or because there has been limited prospective longitudinal data comparing the pre-gravid and antepartum status of women that go on to develop these conditions. Rigorous prospective cohort studies in which women undergo serial systematic evaluation in the pre-conception period, throughout pregnancy and into the postpartum are ideally needed to test this hypothesis of pre-conception origins of PE and GDM. In this context, we are creating a pre-conception cohort, involving about 5000 couples who plan to have a baby within six months in Liuyang county in the Chinese province of Hunan. Results from this pre-conception cohort program should be able to provide definitive answer to the question of whether the underpinnings of PE and GDM originate prior to pregnancy. Ultimately, the significance of addressing this hypothesis is underscored by its potential implications for targeted interventions that could be designed to (i) prevent the deleterious effects of PE/GDM and (ii) thereby interrupt the vicious cycle of disease that links affected women and their offspring.

Premature mortality in refractory partial epilepsy: does surgical treatment make a difference?

BACKGROUND

Epilepsy carries an increased risk of premature death. For some people with intractable focal epilepsy, surgery offers hope for a seizure-free life. The authors aimed to see whether epilepsy surgery influenced mortality in people with intractable epilepsy.

METHODS

The authors audited survival status in two cohorts (those who had surgery and those who had presurgical assessment but did not have surgery).

RESULTS

There were 40 known deaths in the non-surgical group (3365 person years of follow-up) and 19 in the surgical group (3905 person-years of follow-up). Non-operated patients were 2.4 times (95% CI 1.4 to 4.2) as likely to die as those who had surgery. They were 4.5 times (95% CI 1.9 to 10.9) as likely to die a probable epilepsy-related death. In the surgical group, those with ongoing seizures 1 year after surgery were 4.0 (95% CI 1.2 to 13.7) times as likely to die as those who were seizure-free or who had only simple partial seizures. Time-dependent Cox analysis showed that the yearly outcome group did not significantly affect mortality (HR 1.3, 95% CI 0.9 to 1.8).

CONCLUSION

Successful epilepsy surgery was associated with a reduced risk of premature mortality, compared with those with refractory focal epilepsy who did not have surgical treatment. To some extent, the reduced mortality is likely to be conferred by inducing freedom from seizures. It is not certain whether better survival is attributable only to surgery, as treatment decisions were not randomised, and there may be inherent differences between the groups.

Fetal macrosomia and adolescence obesity: results from a longitudinal cohort study

OBJECTIVE

To assess the association between fetal macrosomia and adolescent obesity.

DESIGN

Longitudinal cohort study of the association between macrosomia and adolescent obesity.

SUBJECTS

Between 1 October 2005 and 1 February 2007, a follow-up study of live-born infants born in 1993-1995 in Wuxi, a suburban area of Shanghai, was conducted. Subjects with birth weight > 4000 g were selected as the exposed. For each exposed subject, one subject with a birth weight of 2500-4000 g, matched by year of birth, sex of infant, and type of institute at birth, was chosen as non-exposed. Clinical data were collected by structured interview and physical examination. Obesity was defined as body mass index (weight (kg)/height (m(2))) higher than the sex-age-specific criteria by the working group on obesity in China. Distribution of baseline characteristics and adolescent obesity rate between the exposed and non-exposed groups was compared.

RESULTS

A total of 1435 pairs of exposed and non-exposed subjects were included in the final analysis. No major difference in baseline characteristics (other than birth weight) was found between the exposed and non-exposed groups. Obesity rate was significantly higher in the exposed group (2.9%) than in the non-exposed group (1.6%). Adolescent obesity rates were 1.4, 1.9, 2.6, and 5.6%, respectively, in study subjects with a birth weight of 2500-3499, 3500-3999, 4000-4499, and > or =4500 g. The association between birth weight and adolescent obesity remained essentially the same when mother's demographic and anthropometric factors, breast feeding, and adolescent life-style factors were adjusted.

CONCLUSION

Compared with infants of normal birth weight, infants with birth weight >4000 g, especially those >4500 g, are at increased risk of adolescent obesity.

Pregnancy-induced hypertension and infant mortality in triplets

OBJECTIVE

To assess the effects of pregnancy-induced hypertension on infant mortality in triplets stratified by gestational age at birth.

METHODS

A retrospective cohort study was conducted using the linked 1995-2000 US birth/infant death database. Generalized estimating equations were used to evaluate the observed association.

RESULTS

Pregnancy-induced hypertension was associated with lesser neonatal mortality (odds ration [OR]: 0.34, 95% CI: 0.21, 0.54), postneonatal mortality (OR: 0.54, 95% CI: 0.30, 0.99) and infant mortality (OR, 0.37, 95% CI: 0.25, 0.55) in triplets. It was also associated with a decreased risk of neonatal death (OR, 0.38; 95% CI, 0.21-0.67), postneonatal death (OR, 0.45; 95% CI, 0.21-0.97), and infant death (OR, 0.39; 95% CI, 0.24-0.64) in early preterm triplets, whereas the association was not significant in late preterm or in full-term triplets.

CONCLUSION

Pregnancy-induced hypertension is associated with a decreased risk of infant mortality in triplets. This effect varies with gestational age at birth.

Association of caesarean delivery for first birth with placenta praevia and placental abruption in second pregnancy

OBJECTIVE

To quantify the risk of placenta praevia and placental abruption in singleton, second pregnancies after a caesarean delivery of the first pregnancy.

DESIGN

Retrospective cohort study.

SETTING

Linked birth and infant mortality database of the USA between 1995 and 2000.

POPULATION

A total of 5,146,742 singleton second pregnancies were available for the final analysis after excluding missing information.

METHODS

Multiple logistic regressions were used to describe the relationship between caesarean section at first birth and placenta praevia and placental abruption in second-birth singletons.

MAIN OUTCOME MEASURES

Placenta praevia and placental abruption.

RESULTS

Placenta praevia was recorded in 4.4 per 1000 second-birth singletons whose first births delivered by caesarean section and 2.7 per 1000 second-birth singletons whose first births delivered vaginally. About 6.8 per 1000 births were complicated with placental abruption in second-birth singletons whose first births delivered by caesarean section and 4.8 per 1000 birth in second-birth singletons whose first births delivered vaginally. The adjusted odds ratio (95% CIs) of previous caesarean section for placenta praevia in following second pregnancies was 1.47 (1.41, 1.52) after controlling for maternal age, race, education, marital status, maternal drinking and smoking during pregnancy, adequacy of prenatal care, and fetal gender. The corresponding figure for placental abruption was 1.40 (1.36, 1.45).

CONCLUSION

Caesarean section for first live birth is associated with a 47% increased risk of placenta praevia and 40% increased risk of placental abruption in second pregnancy with a singleton.

Rufinamide

Rufinamide is a new antiepileptic drug that is effective in acute animal seizure models and also in the kindling model of epilepsy with a high protective index. Its mechanism of action is largely unknown; studies suggest an effect at voltage-gated sodium channels, but whether this is its main mode of action remains to be determined. Rufinamide can be administered twice daily and has minimal drug interactions (it does, however, interact with the contraceptive pill). Food markedly increases absorption, which may complicate clinical use. Trials indicate that rufinamide is effective as adjunctive therapy in partial epilepsy and the Lennox-Gastaut syndrome with minimal adverse effects including headache, dizziness and fatigue. In addition, rufinamide has a favorable cognitive side-effect profile. However, it remains uncertain whether rufinamide offers significant advantages over other current antiepileptic drugs, and the results of further clinical trials are awaited.

Regulation and role of REST and REST4 variants in modulation of gene expression in in vivo and in vitro in epilepsy models

Repressor element-1 silencing transcription factor (REST) is a candidate modulator of gene expression during status epilepticus in the rodent. In such models, full-length REST and the truncated REST4 variant are induced and can potentially direct differential gene expression patterns. We have addressed the regulation of these REST variants in rodent hippocampal seizure models and correlated this with expression of the proconvulsant, substance P encoding, PPT-A gene. REST and REST4 were differentially regulated following kainic acid stimulus both in in vitro and in vivo models. REST4 was more tightly regulated than REST in both models and its transient expression correlated with that of the differential regulation of PPT-A. Consistent with this, overexpression of a truncated REST protein (HZ4, lacking the C-terminal repression domain) increased expression of the endogenous PPT-A gene. Similarly the proximal PPT-A promoter reporter gene construct was differentially regulated by the distinct REST isoforms in hippocampal cells with HZ4 being the major inducer of increased reporter expression. Furthermore, REST and REST4 proteins were differentially expressed and compartmentalized within rat hippocampal cells in vitro following noxious stimuli. This differential localization of the REST isoforms was confirmed in the CA1 region following perforant path and kainic acid induction of status epilepticus in vivo. We propose that the interplay between REST and REST4 alter the expression of proconvulsant genes, as exemplified by the PPT-A gene, and may therefore regulate the progression of epileptogenesis.

Do seizures in patients with refractory epilepsy vary between wakefulness and sleep?

AIM

To determine the effects of sleep and wakefulness on seizures in patients with refractory epilepsy recorded while undergoing video-electroencephalography (EEG) telemetry.

METHODS

The video-EEG data of patients who had two or more seizures during video-EEG telemetry (n = 270) were reviewed. Fifty seven patients who had seizures both in wakefulness and sleep were identified. The video and ictal EEG data were reviewed, paying specific attention to type of seizures, duration, semiology, lateralisation and number of seizures.

RESULTS

Three hundred and sixty two seizures were recorded; 237 seizures while awake and 125 while sleeping. Secondary generalisation occurred more often in sleep than in wakefulness (p < 0.01). Overall, there was no significant effect of sleep on the duration of seizures or ictal EEG change. Sleep and awake seizures differed in only eight patients.

CONCLUSION

Secondary generalisation occurred more often in sleep than in wakefulness, perhaps due to the facilitated spread of seizures during sleep. For the most part, however, seizures recorded during sleep did not differ from those recorded during wakefulness.

Treatment of seizure emergencies: Convulsive and non-convulsive status epilepticus

Status epilepticus (SE), defined as recurrent epileptic seizures without complete recovery between seizures, is one of the most serious manifestations of epilepsy. Generalized convulsive status epilepticus (GCSE) is the most common and most life-threatening form of SE, and aging increases the mortality risk. In a recent study of treatment of GCSE, 226 of 518 evaluable patients (43.6%) were of age 65 or older. In the 157 elderly patients with overt GCSE, phenobarbital was successful as first-line treatment in 71.4%, lorazepam in 63%, diazepam and phenytoin in 53.3%, and phenytoin alone in 41.5%. Phenobarbital and lorazepam were more successful than phenytoin alone. In the 69 elderly patients with subtle GCSE, success as the first treatment was 30.8% for phenobarbital, 14.3% for lorazepam, 11.8% for phenytoin, and 7.7% for diazepam and phenytoin. Overall, the results were similar to those reported for the entire study. Lorazepam, because of ease of use, is probably the best drug for the initial treatment of overt GCSE in the elderly; phenobarbital may be the best drug for subtle GCSE in this group, but more data are needed. The term "nonconvulsive SE" has been used to include complex partial SE and absence SE - both of which present as an "epileptic twilight state" - and SE in comatose patients. The diagnosis can be challenging, particularly in the elderly, as overlapping clinical features and electroencephalogram patterns can be seen in SE and in a variety of encephalopathic conditions. There is a suggestion that aggressive treatment of elderly patients with nonconvulsive SE may worsen prognosis. Clearly, there is a need for more data to better understand management of elderly patients with both convulsive and nonconvulsive SE.

Heparin for pregnant women with acquired or inherited thrombophilias

BACKGROUND

Thrombophilias, which are associated with a predisposition to thrombotic events, have been implicated in adverse obstetrical outcomes such as intrauterine growth restriction, stillbirth, severe early onset pre-eclampsia, and placental abruption. Heparin administration in pregnancy may reduce the risk of these events.

OBJECTIVES

The objective of this review was to assess the effects of heparin on pregnancy outcomes for women with a thrombophilia.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group trials register (July 2002), MEDLINE, EMBASE, CINAHL, Scidex (via OVID Technologies - July 2002) and reference lists and personal files.

SELECTION CRITERIA

Randomized controlled trials comparing heparin with placebo or no treatment, or randomized controlled trials comparing any two treatments. Quasi randomized studies would be included.

DATA COLLECTION AND ANALYSIS

Data would be abstracted from identified studies and recorded on a paper form by two reviewers.

MAIN RESULTS

No studies were included.

REVIEWER'S CONCLUSIONS

There are no completed trials to determine the effects of heparin on pregnancy outcomes for women with a thrombophilia.

Disease modification in partial epilepsy

With the growth in antiepileptic drug treatment, the question arises as to what extent we are merely treating the symptom (i.e. the seizures) rather than the underlying disease process (i.e. epileptogenesis). Epileptogenicity can be considered as the process whereby structural and functional changes occur following an insult that in some cases result in epilepsy. Epileptogenicity also describes some of the changes and processes that contribute to the progression observed in some epilepsies. These processes have been modelled in animals mostly by the kindling model of epilepsy, in which repetition of subconvulsive stimuli results in a progressive epileptic state and eventually leads to spontaneous seizures. However, it is not clear that kindling has a human correlate, so models in which an initial insult (status epilepticus, hyperthermia, hypoxia, trauma) is followed by the development of lowered seizure threshold and, in some instances, spontaneous seizures have been used. These models seem to support the "second hit" hypothesis, in which there is an initial insult resulting in lowered seizure threshold, and then a later insult, the "second hit", that results in the expression of epilepsy. These models also support the concept of a latent period during which there could be targeted therapies to prevent the epileptogenic process. Although the occurrence of neuronal damage is one such target, neuronal damage is not necessary for epileptogenesis, and other mechanisms are at play. At the present time, it is not known whether targeted therapies may also affect compensatory processes, such as brain repair. Clearly, this would be a potential risk of such strategies. Epidemiological evidence and trials indicate that our present antiepileptic drugs are not effective in preventing epileptogenesis; antiepileptic drugs were, however, not designed for this purpose. Data from animal experiments suggest that treatment of non-convulsive status epilepticus following specific insults may prevent epileptogenesis. The relevance of this for the human condition remains uncertain, but non-convulsive status epilepticus is probably an under-recognized and probably under-treated condition. Perhaps one of the most salutary findings has been the observation of decreased childhood epilepsy with improved neonatal care. This highlights the importance of medical care at the time of an insult, and of prevention of the insults. This review discusses the data that support the concepts underlying epileptogenesis and the model systems that are presumed to reflect the human condition. Particular attention is paid to the potential for interrupting the processes underlying epileptogenesis.

Diagnosis and treatment of nonconvulsive status epilepticus

Nonconvulsive status epilepticus (SE) is not uncommon and comprises at least one-third of all cases of SE. However, nonconvulsive SE consists of very different syndromes, a common feature being the difficulty in making the diagnosis. In this review, nonconvulsive SE is divided into typical absence SE, complex partial SE, nonconvulsive SE in patients with learning difficulties (including electrical SE during sleep, atypical absence SE and tonic SE), and nonconvulsive SE in coma. These conditions have different prognoses and treatments. The diagnosis of these conditions is critically dependent on EEG. When the EEG demonstrates typical ictal patterns, the diagnosis is usually straightforward. However, in many circumstances the EEG has to be differentiated from encephalopathic patterns, and this differentiation can prove troublesome, although the clinical and electrographic response to treatment can prove helpful. Nonconvulsive SE in patients with learning difficulties possibly provides the greatest diagnostic difficulty; the clinical presentation can be subtle resulting in the diagnosis being frequently missed. Whether the neuronal damage that occurs in convulsive SE and in animal models of limbic SE also occurs in nonconvulsive SE in humans is still a matter of debate. There are critical differences between the animal models and the human condition. Indeed, the prognosis of nonconvulsive SE is usually dependent on the underlying aetiology rather than the persistence of electrographic discharges. Because of these doubts, a more conservative approach to the treatment of particular types of nonconvulsive SE (those with a better prognosis) has been taken in this article. Thus, in most instances, oral benzodiazepines for the treatment of typical absence SE and complex partial SE are recommended. In some circumstances intravenous medication is necessary, but in neither condition is anaesthetic coma recommended. This contrasts with nonconvulsive SE in coma in which a more aggressive approach is suggested. Until there are more relevant animal models, and controlled trials of conservative versus more aggressive treatment, treatment regimens for nonconvulsive SE will remain largely speculative.

Postprandial venous ammonia concentrations in the diagnosis of hepatobiliary disease in dogs

A postprandial ammonia tolerance test (PPATT) was performed on normal dogs and dogs with signs that suggested they may have liver disease. All dogs underwent transcolonic scintigraphy, liver biopsy, or both and were assigned to extrahepatic disease, primary hepatocellular, and congenital portosystemic vascular anomalies (PSVA) groups. Each dog was fed a chicken and rice diet providing 25% of its estimated daily metabolizable energy requirement (MER) as an ammonia challenge. This is practical in patients with liver disease because ammonium chloride administration often causes vomiting or ammonia toxicity. Venous ammonia concentrations were measured before feeding and every 2 hours after feeding for 8 hours. No difference in mean ammonia concentrations between dogs with extrahepatic disease and control dogs was found. Therefore, the specificity of the PPATT was 100%. Dogs with hepatocellular disease showed no change in mean ammonia concentration at any time point, before or after feeding, but sensitivity was greatest when venous ammonia was measured 6 hours after feeding (sensitivity before feeding, 28%, and after feeding, 36%). Among dogs with congenital PSVA, mean ammonia concentrations were higher than the reference range at all time points before and after feeding, and peak mean ammonia concentration occurred 6 hours after feeding. In this group, the sensitivity of the PPATT was 81% before feeding and 91% 6 hours after feeding. This study demonstrates that the measurement of venous ammonia concentration is a useful test to detect congenital PSVA, and the sensitivity of the test may be improved by sampling 6 hours after feeding. The PPATT has poor sensitivity in detecting primary hepatocellular disease.

A three-step kinetic mechanism for selective inhibition of cyclo-oxygenase-2 by diarylheterocyclic inhibitors

Cyclo-oxygenase (COX) enzymes are the targets for non-steroidal anti-inflammatory drugs (NSAIDs). These drugs demonstrate a variety of inhibitory mechanisms, which include simple competitive, as well as slow binding and irreversible inhibition. In general, most NSAIDs inhibit COX-1 and -2 by similar mechanisms. A unique class of diarylheterocyclic inhibitors has been developed that is highly selective for COX-2 by virtue of distinct inhibitory mechanisms for each isoenzyme. Several of these inhibitors, with varying selectivity, have been utilized to probe the mechanisms of COX inhibition. Results from analysis of both steady-state and time-dependent inhibition were compared. A generalized mechanism for inhibition, consisting of three sequential reversible steps, can account for the various types of kinetic behaviour observed with these inhibitors.

The attitude of courts in England to compensation for post-traumatic epilepsy

The attitudes of courts in England to the assessment of damages for post-traumatic epilepsy have dramatically changed over the last 20-30 years. In assessing damages for post-traumatic epilepsy the courts are faced with a number of considerations: epilepsy can appear several years after the injury; epilepsy is not a homogeneous condition; the eventual prognosis is unknown; the epilepsy may not have been directly due to the trauma; and epilepsy affects life expectancy and employment. Damages were originally fixed at the point of compensation, and these rather crude calculations led to both over- and under-compensation. This situation was improved in 1985, when courts were permitted to award damages on the assumption that epilepsy would not occur or worsen, and further damages should these assumptions prove to be incorrect. The courts in England still depend, however, upon the evidence of expert witnesses chosen by the plaintiff and defendant. A tension thus exists between the duty of expert witnesses to the court and the understandable inclination of expert witnesses to support the party that has instructed them. The Woolf report has led to changes in the responsibilities of expert witnesses, and will hopefully remedy many of the inconsistencies and inequities that occur.

Monosynaptic GABAergic signaling from dentate to CA3 with a pharmacological and physiological profile typical of mossy fiber synapses

Mossy fibers are the sole excitatory projection from dentate gyrus granule cells to the hippocampus, where they release glutamate, dynorphin, and zinc. In addition, mossy fiber terminals show intense immunoreactivity for the inhibitory neurotransmitter GABA. Fast inhibitory transmission at mossy fiber synapses, however, has not previously been reported. Here, we show that electrical or chemical stimuli that recruit dentate granule cells elicit monosynaptic GABA(A) receptor-mediated synaptic signals in CA3 pyramidal neurons. These inhibitory signals satisfy the criteria that distinguish mossy fiber-CA3 synapses: high sensitivity to metabotropic glutamate receptor agonists, facilitation during repetitive stimulation, and NMDA receptor-independent long-term potentiation. GABAergic transmission from the dentate gyrus to CA3 has major implications not only for information flow into the hippocampus but also for developmental and pathological processes involving the hippocampus.

Propofol in subanesthetic doses terminates status epilepticus in a rodent model

Status epilepticus is commonly refractory to first-line therapy, and thus better treatments are needed. We have investigated an experimental model of drug-resistant self-sustaining status epilepticus (SSSE) induced by 2 hours of perforant path stimulation. Propofol in subanesthetic doses administered shortly after the end of stimulation and also after a further 3 hours of SSSE terminated the SSSE without recurrence. This finding calls for a trial of propofol in refractory status epilepticus and also raises the possibility of using it as first-line therapy.

Maternal plasma homocysteine levels in women with preterm premature rupture of membranes

Homocysteine is a sulfur-containing amino acid produced by the breakdown of methionine. Plasma homocysteine levels can be elevated due to a variety of genetic and nutritional factors. Poor nutrition from diets low in folate and vitamin B12 can lead to hyperhomocysteinemia. Mildly elevated levels of homocysteine have been implicated in a number of disease processes such as atherosclerotic vascular disease and adverse obstetrical outcomes. High levels of plasma homocysteine are also associated with abnormal collagen cross-linking. Due to homocysteine's effects on connective tissue integrity, it is hypothesized that hyperhomocysteinemia in pregnancy is associated with preterm premature rupture of membranes (PPROM). Hyperhomocysteinemia, therefore, could be a treatable cause of this important public health concern.

The role of mammalian ionotropic receptors in synaptic plasticity: LTP, LTD and epilepsy

Synaptic plasticity is the foremost candidate mechanism to explain the rapid acquisition of memories. In the mammalian brain, the NMDA subclass of glutamate receptors plays a central role in the induction of several forms of use-dependent plasticity. The finding that modifications in synaptic strength are largely expressed by receptors of the AMPA subclass has focused attention on molecular mechanisms that affect their function and targeting. Receptor plasticity has also been reported in pathological situations, notably in animal and human forms of epilepsy. Which of these changes are causally implicated in the generation of seizures, and which may be compensatory or neuroprotective adaptations, has not been fully resolved.

Comparison of serum, cerebrospinal fluid and brain extracellular fluid pharmacokinetics of lamotrigine

We investigated the rate of penetration into and the intra-relationship between the serum, cerebrospinal fluid (CSF) and regional brain extracellular fluid (bECF) compartments following systemic administration of lamotrigine in rat. The serum pharmacokinetics were biphasic with an initial distribution phase, (half-life approximately 3 h), and then a prolonged elimination phase of over 30 h. The serum pharmacokinetics were linear over the range 10 - 40 mg kg(-1). Using direct sampling of CSF with concomitant serum sampling, the calculated penetration half-time into CSF was 0.42+/-0.15 h. At equilibrium, the CSF to total serum concentration ratio (0.61+/-0.02) was greater than the free to total serum concentration (0.39+/-0.01). Using in vivo recovery corrected microdialysis sampling in frontal cortex and hippocampus with concomitant serum sampling, the calculated penetration half-time of lamotrigine into bECF, 0.51+/-0.11 h, was similar to that for CSF and was not area or dose dependent. At equilibrium, the bECF to total serum concentration ratio (0.40+/-0.04) was similar to the free to total serum concentration (0.39+/-0.01), and did not differ between hippocampus and frontal cortex. The species specific serum kinetics can explain the prolonged action of lamotrigine in rat seizure models. Lamotrigine has a relatively slow penetration into both CSF and bECF compartments compared with antiepileptic drugs used in acute seizures. Furthermore, the free serum drug concentration is not the sole contributor to the CSF compartment, and the CSF concentration is an overestimate of the bECF concentration of lamotrigine.

Large-scale purification of myeloperoxidase from HL60 promyelocytic cells: characterization and comparison to human neutrophil myeloperoxidase

A large-scale purification procedure was developed for the isolation of myeloperoxidase from HL60 promyelocytic cells in culture. Initial studies showed the bulk of peroxidase-positive myeloperoxidase activity to be located in the cetyltrimethylammonium bromide solubilized particulate fraction of cell homogenates. The myeloperoxidase was then chromatographically purified using concanavalin A followed by gel filtration. SDS-PAGE analysis of the final preparation showed the presence of only two proteins with molecular masses of approximately 55 and 15 kDa, corresponding to the large and small subunits of myeloperoxidase. These data, along with Reinheit Zahl (RZ) values (A(430)/A(280)) of greater than or equal to 0.72, indicate that the myeloperoxidase prepared by this method is apparently homogeneous. Preparations routinely yielded 12-20 mg of pure myeloperoxidase per 10 ml of cell pellet. The HL60 myeloperoxidase was shown to be indistinguishable from purified human neutrophil myeloperoxidase by size exclusion chromatography, analytical ultracentrifugation, SDS-PAGE, Western blot, and NH(2)-terminal sequence analysis. The activities of the two myeloperoxidase samples, as measured using either the tetramethylbenzidine or the taurine chloramine assay, were indistinguishable. Finally, both enzymes responded identically to dapsone and aminobenzoic acid hydrazide, known inhibitors of myeloperoxidase. A protocol is presented here for the rapid, large-scale purification of myeloperoxidase from cultured HL60 cells, as well as evidence for the interchangeability of this myeloperoxidase and that purified from human neutrophils.

Multiple endocrine neoplasia type 1 in a crossbred dog

Multiple endocrine neoplasia type 1 was diagnosed in a 12-year-old male crossbred dog. Relevant history included polyuria and polydipsia of four months' duration. Physical examination revealed abdominal enlargement, seborrhoea and polypnoea. Diagnostic tests indicated hypercalcaemia, elevated serum alkaline phosphatase and alanine aminotransferase, an exaggerated response to adrenocorticotropic stimulation of the adrenal gland, lack of cortisol suppression with a low dose dexamethasone suppression test and suppression of cortisol secretion with a high dose dexamethasone test. An enlarged right parathyroid gland was removed surgically and confirmed histopathologically to be a parathyroid adenoma. The pituitary-dependent hyperadrenocorticism was treated successfully with mitotane for 14 months before the patient was euthanased for an unrelated problem.

Vertebral physitis with epiphyseal sequestration and a portosystemic shunt in a Pekingese dog

Vertebral physitis with bone sequestration and a portosystemic shunt were diagnosed in an 18-month-old female Pekingese dog. The latter was determined by the presence of low blood urea nitrogen, elevated serum bile acids, microhepatica and an increased portosystemic shunt fraction. It was managed with a home-cooked low protein diet. Vertebral physitis and bone sequestration was diagnosed by the presence of thoracolumbar hyperaesthesia, radiographic and scintigraphic changes, isolation of Staphylococcus intermedius from blood and the third lumbar vertebra, and histopathological examination of a surgical biopsy. A partial sequestrectomy was performed and a six-month course of amoxycillin-clavulanate was prescribed. The dog was pain-free and showed partial resolution of the radiographic signs four months after the discontinuation of antibiotics.

A canarypox vaccine expressing multiple human immunodeficiency virus type 1 genes given alone or with rgp120 elicits broad and durable CD8+ cytotoxic T lymphocyte responses in seronegative volunteers

Induction of CD8+ cytotoxic T cells is considered one of the important correlates for the protective efficacy of candidate human immunodeficiency virus type 1 (HIV-1) vaccines. To induce CD8+ cytotoxic T lymphocytes (CTLs) along with neutralizing antibody and CD4+ T cell help, a live canarypox virus construct expressing gp120, transmembrane gp41, the gag and protease genes, and sequences containing CTL epitopes in nef and pol was given simultaneously with, or followed by, rgp120 SF2. CD8+ CTLs were detected in 61% of volunteers at some time during the trial. Three to 6 months after the last immunization, the gene-specific responses were gag, 26/81; env, 17/77; nef, 12/77; and pol, 3/16. Simultaneous immunization with the canarypox vector and the subunit, beginning with the initial immunization, resulted in earlier antibody responses. In summary, a strategy of immunization with a canarypox vector expressing multiple genes of HIV-1 given with gp120 results in durable CD8+ CTL responses to a broad range of epitopes.